The present invention relates generally to a bushing block which combines the bushing and bearing cap components of a trunnion assembly of an independent suspension.
In an independent suspension, a trunnion assembly is employed to connect the suspension spring and shock absorber assembly to the lower control arm assembly. Each trunnion assembly includes a pair of trunnion pins, and a bushing installed over each trunnion pin. A bearing cap secures the trunnion pin and the bushing to the lower control arm assembly by a pair of cap screws.
The trunnion pin is greased by adding lubricant to a grease fitting located on the upper portion of the bushing. In prior trunnion assemblies, grease grooves are machined on the exterior surface of the trunnion pin to allow grease to flow over the trunnion pin.
There are several drawbacks to employing the prior art trunnion assembly. For one, as the bushing and bearing cap are separate components, numerous parts and steps are required for assembly. Additionally, the grease grooves are machined into the exterior surface of the trunnion pin, requiring an additional machining step. Finally, a face seal utilized on the trunnion assembly acts as an axial bearing surface.
Hence, there is a need in the art for a bushing block which combines the bushing and bearing cap components of a trunnion assembly of an independent suspension.
The present invention relates generally to a bushing block which combines the bushing and bearing cap components of a trunnion assembly of an independent suspension.
A bushing block of the present invention integrates a bushing and a bearing cap into a single component. Preferably, the block is formed of powdered metal. A grease fitting aperture is formed into the upper portion of the bushing block and a grease fitting is installed therein. A pair of cap screw apertures are drilled in the side arms of the bushing block. An annular face seal is pressed onto the trunnion pin, and the bushing block is then mounted on the trunnion pin, with the bushing block contacting the face seal.
The trunnion assembly is positioned on the lower control arm assembly such that the cap screw apertures of the bushing block substantially align with cap screw apertures drilled into the lower control arm assembly. Cap screws are inserted in the apertures, securing the bushing block to the lower control arm assembly.
By employing a bushing block, a more compact design is possible. Additionally, the bushing blocks provides both axial and radial constraint for the trunnion pin.
A further feature of the invention allows for grease grooves formed on the interior surface of the bushing block. The grooves allow grease to flow down the exterior surface of the trunnion pin to grease the assembly.
Accordingly, the present invention provides a bushing block which combines the bushing and bearing cap components of a trunnion assembly of an independent suspension.
These and other features of the present invention will be best understood from the following specification and drawings.